Process for manufacturing photographic glass pictures and the like with colored background



Patented Feb. 23, 1926.

1,574,156 oi'rsosrarns PATENT OFFICE. f

WERNER KIESLENG, 0F BERLIN-NEUKOLLN, GERMANY, ASSIGNOR. TO, N. V. HANDEL- lVIAATSCI-IAPPIJ, MERCATOR, OF ZANDVOORT, NETHERLANDS.

rnoonss roza MANUFACTURING rrroroenarnro erase rrornnns. AND THE LIKE wrrrr cononnn BACKGROUND.

pose a glass plate or the like coated with a layer of bichromated gelatine and then to wash out the unaltered bichromate from those parts of the glass plate or the like which have not been exposed to light, hereafter to color by means of a dye solution,

those portions of the gelatinelayer which have not been exposed tolightand are still permeable and absorbent to liquid, whereupon the whole plate or the like is painted on the back with a background color. This manufacturing method presents however the inconvenience that thewashing out of the bichroinate from the unexposed portions of the coating'cannot be carried through completely so that these portions of the coating preserve a yellowish shade which is prejudicial for the formation of the background especially when the backgre'iund has to be painted in delicate light tints, as silver,

white or the like.

According to the present invention this inconvenience is avoided by using for making the light-sensitive layer a glue, especially liquid glue or a glue which is soluble incold water, as for instance isinglass, which is known to possess the property to become insoluble in water when it is exposed to light in a bichroinated state, but to remain perine- Application filed December 18, 1924. Serial No. 756,827.

protected from light are absolutely free from coating andconsequently colorless, even the most delicate tints become effective at the painting of the background. It has also been proposed to use bichromated fish glue and the like instead of hichroinate gelatine for the production of pictures on'transparent carriers. But those portions of the coating which had been protected from light were not entirely washed away in this case but merely the bichromate.

was washed out therefrom. This known process further did not relate to the manufacturing of glass pictures or the like with colored background but merely to the production' of kinematographic films with transparent background. With :such films the weak yellowish'tint of the portions of the picture which had not been eXposedto light were not of greatconsideration. It has further been proposed to destroy the residue of the free chromate salts by treatingthe plates or the like with sodium bisulphite and to. bleach the picture in this manner. This required however a special additional treatment which is avoided bythe process according to the present invention;

The characteristic feature of the present invention consequently consists in a special combination of several processes known per se whereby the above-stated special effect is obtained. .1

The new manufacturing method can be carried out .for instance in the'following manner: The plane, absolutely transparent and cleansurfaoe of a plate of gass, celluloid or other transparent material is firstly coated with an aqueous solution. of ammoniumbichromate fish glue so that avery thin li sensitive fish glue layeris formed on one of the surfaces of the plate. This coating after having dried is exposed under a transparent reticle negative in an ordinary photo-engravers printing frame. The developing of the transparent picture thus obtained on the plate is then effected by thoroughly washing eventually in tepidfwater. Those portions of the fish glue coating which have remained unaltered are removed thereby from' the unexposed portions of the plate together with the unaltered bichroinate salt. The perfectly transparent picture which is thus produced is then colored with convenient dye solutions, for instance with solutions of aniline dyes, the dye being absorbed by those portions of the coating which have been previously exposed to light and in which the. fish glue has lost its solubility in water but preserved its capability of being swelled and impregnated by aqueous solutions.

The thus colored picture which is yet perfectly transparent on those portions which were protected fro-1n light during the exposure, can now either be coated with a paint on the film side for forming a back ground, or a metal colored powder in combination with a suitable agglutinant can be fixed on the same by rolling or the like.

In order toproduce special effects some of those portions of the plate which are free, from coating may be colored in a special manner on the back of the plate before the formation of the background. This can be done mechanically when manufacturing in large quantities, for instance by covering with stencils those portions of the plate I which are not to be colored and by squirting coloring substances upon the free portions of the plate. The entire back of the plate may then be colored for producinga uniform. background in the above indicated manner, for instance by rolling andfixing on the same a metal-powder. Also for such a special coloring of the unexposed portions of the plate it is of special importance that these portions of the plate be perfectly colorless before and not tinted yellowish by a residue of chromate.

After the portions of the plate, .Which have been exposed under the negative and are covered with the insoluble fish glue layer have been colored by'means of dye solutions, these portions may. yet be fixed, if necessary, by means of a special bath, for instance a bath of sulphateof copper in a manner known-per se. g

Instead of glass plates other transparent plates or sheets may be employed for producing the pictures, for instance sheets of celluloid, nitro-cellulose or cellon. If the background is painted so thinly that it remains transparent, pictures can be produced in this manner which are adapted to be used according to the manner of the socalled diaphanous pictures.

The above described method can be used also for the production of multi-colored pictures in such a manner that several partial pictures are produced the one upon the other with the utilization of insoluble transparent intermediate layers, each partial picture being produced by means of a sensitized coating of fish glue or the like in the above indicated manner.

For this purpose I may proceed as follows: The transparent plate of glass or the like is firstly coated on the one surface with a layer of bichromate fish glue, whereupon the plate is exposed under a partial negative, for instance a reticle negative. The transparent picture which is thus produced will then be fixed and developed by thorough washing, the'unaltered chromate salt together with the unaltered portion of the glue-layer being removed thereby from those parts of the plate which were, protected from light during the exposure. The remaining or exposed portions of the coat ing are then colored by means of suitable dye solutions, for instance solutions of aniline dyes. The thus colored picture, which at the not exposed parts is perfectly transparent and absolutly free of any coating is then covered on the coated side with a thin protecting layer of a transparent, preferably colorless and rapidly drying solution, for instance a solution of zapon varnish or the like. On this protecting layer a new coats ing of bichromate fish glue is applied after the protecting layer has dried, and the freshly sensitized coating is then exposed under a second partial negative whereupon the second partial picture is fixed and developed in the same manner as the first one and colored with a differently colored dye solution. This proceeding can be repeated as often as desired, a transparent protecting layer of zapon varnish or the like being always interposed between the different sensitized coatings of the plate so that pictures of so many different colors as desired can be produced on the transparent plate. Those parts of the plate which at the end of the proceeding hiWe yet remained transparent are painted on the coated side in the above indicated manner with an opaque color, for instance a metal powder, to produce the background. 'lhe background can also in this case be painted venient covering stencils as described before.

Having now particularly described and ascertained the nature of my said invention, I declare that what I claim is 1. A process for the photomechanical in some different colors with the aid of concold, the coated side ofthe plate being exposed under a reticle negative, the unaltered glue being then removed from those portions of the plate which were protected from light during the exposure under the reticle negative, the exposed portions being then colored with a dye solution, and the entire coated side of the plate and especially those portions from which the light-sensitive layer has been removed being finally painted with another coloring substance for the production of the background.

2. process for the photomechanical manufacturing of glass pictures and the like with colored background, consisting in a reticle negative, removing the unaltered fish glue from those portions of the plate which were protected from light during the exposure, coloring the exposed portions with a dye solution, and finally painting the entire coated side of the plate and especially those portions from which the light-sensitive layer has been removed with another coloring substance for the production of the background.

A process for the photoinechanical I manufacturing of glass pictures and the 7 like with colored background, consisting in coating the transparent plate or the like with a thin layer of bichroinatc fish glue, exposing the coated side of the plate under a reticle negative, removing the unaltered fish glue from those portions of the plate which were protected from light during the exposure, coloring the exposed port-ions with a dye solution, coloring some of the transparent parts of the plate by means of special paints, and then coating the back of the plate with another background color.

In testimony whereof I have hereunto set my hand.

' WERNER KIESLING. 

